07 July 2013

Pitted Beetle – Dhahran Hills


The Pitted Beetle Adesmia cancellata is becoming more obvious by the day at present and is a day active desert beetle that is common throughout Arabia and very common in Dhahran. It can be found anywhere there is vegetation and it feeds off organic debris from plants. It has many physical problems to contend with in the hot deserts where it lives, including extremes of temperature, low humidity, shortage or absence of free water, and the environmental factors that accentuate these - such as strong winds, sand-storms, lack of shade, rocky and impenetrable soils. Nevertheless, Pitted Beetle is among the most successful animals of the desert, and often the only ones to be seen during the day. They are able to withstand thermal extremes that would rapidly cause the death of most other arthropods including insects. They have remarkably low rates of transpiration and can withstand a considerable reduction in the water content of their tissues. Generally, black beetles are extremely well adapted to live under very hot and dry conditions. The genus Adesmia belongs to the type of "fast runners" which can reach speeds of one meter per second. They use their long legs to lift their body well clear of the hot ground, and increase the clearance as the temperature rises. Interestingly these beetles seem to not be liked by the many species of Shrikes that pass through the area on migration and I have never seen one being eaten even though they are common and quite obvious. Other beetles are regularly taken but not this species for some reason.